Hydrofoil bow door

ABSTRACT

The present invention discloses the method of providing greater structural strength and resistance to fluid leakage in the closure junction of bow or stern doors of a marine, air, or surface vessel by locating the closure junction away from the longitudinal axis of the vessel.

ilnite States atet 11 1 1111 3,837,313

Williams Sept. 24, 1974 HYDROFOIL BOW DOOR 3,280,777 10/1966 Matzer 114 435 x 1 1 Inventor John Williams Bellevuet Wash- 333351333 lfiiii 53%?3'521'5311111:11:11:13?'11 432 52 E [73] Assignee: The Boeing Company, Seattle,

Wash- Primary Examiner-Trygve M. Blix 22 Filed; June 25 1973 Assistant ExaminerBarry L. Kelmachter Attorney, Agent, or Firm-Donald A. Streck 211 App]. No.2 373,549

52 US. (:1 114/665 111, 49/367, 244/129 D [57] ABSTRACT 'f Cl B63!) 1363b The present invention discloses the method of provid Fleld 05 Search 114/665 43.5, ing greater structural strength and resistance to fluid 244/137 R, 129 D, 118 49/366, leakage in the closure junction of bow or stem doors 367 of a marine, air, or surface vessel by locating the closure junction away from the longitudinal axis of the References e eL UNITED STATES PATENTS 2,781,226 2 1957 Tydon 244/118 R x 4 Clams 6 Drawmg F'gures EAIENn-msmmsu Y 3. 837 31 3 sum m I-IYDROF OIL BOW DOOR BACKGROUND OF THE INVENTION a. Field of the Invention The present invention relates to doors, and more particularly to bow and stem doors of marine, air, and surface vessels.

b. Description of the Prior Art The present invention was conceived to solve a particular problem associated with the bow doors of a marine hydrofoil vessel and the discussion and preferred embodiment will be directed to that configuration. It will be seen, however, that the same method of fabrication and attendant benefits apply equally to both bow and stern doors of any vessel operating in a fluid environmentwhere an aerodynamic shape is desired or required.

In a typical marine hydrofoil, the bow foil and strut assembly can be moved from a lowered or foil-borne position to a raised or hull-borne position. In the raised position, the foil and strut assembly are located behind a pair of doors which provide an aerodynamically smooth hull design above and below the waterline at the bow of the vessel. The doors must be capable of being opened and closed mechanically to permit the entrance and egress of the foil and strut assembly. In the closed position, the doors must lock securely since high forces are exerted by the water when the vessel is hull-borne.

In the prior art, such bow doors were fabricated with the line of closure along the longitudinal axis ofthe vessel. Since the hull tends to be knife edged along this same line, such a closure junction is prone to numerous problems. First, it is structurally weak and easily damaged by minor impact. Second, it is subject to maximum fluid pressure and, therefore, tends to leak and open from such pressures. Third, it is thin in cross section, thereby reducing the size of the locking mechanism which can be provided therein.

In the present invention, a generally conventional door and actuating mechanism are employed in the usual manner. At the point of closure, however, the doors are not symmetrical about the vessels longitudinal axis as is the usual case. Rather, the closure junction is located to one side of the longitudinal axis along a line substantially normal to the vessels hull surface. In this manner, one door ismore forward of the other on a bow door and more aft of the other on a stern door. This extended door forms the full bow point or stem point of the vessel and contains a keel member for strength. The closure junction, being located normal to the hull surface, is subject to a shearing force rather than a wedging or longitudinal force.

It is, therefore, an object of the present invention to provide a closure for the bow and stem doors of vessels in which a keel member can be incorporated to provide structural strength to the doors.

Another object of the invention is to provide a closure for the bow and stern doors of vessels with reduced opening tendencies.

A further object of the invention is to provide a closure for the bow and stem doors of vessels with high resistance to damage and fluid leakage.

Another object of the present invention is to provide a closure for the bow and stem doors of vessels with a large cross sectional area to provide space for a sub stantial locking mechanism while maintaining an aerodynamically desirable bow design.

It is a further object of the present invention to accomplish the ends indicated above by simple, rugged, and reliable mechanism which can be depended upon to operate satisfactorily with a minimum of attention throughout the life of the vessel.

With such objects in mind, and others as will appear more fully hereinafter, the invention comprises the novel door closure junction and associated mechanism of the type indicated above, as shown in a typical example in the accompanying drawings, and as will be more fully explained hereinafter, and the principles whereof constituting this invention are set forth in the appended claims.

DESCRIPTION OF THE DRAWINGS The invention will be understood from the following description taken in conjunction with the accompanying drawings, wherein:

FIG. 1 is a view of the bow of a marine hydrofoil vessel from the starboard side showing the doors which are the subject of the present invention in their fully open position. The strut and foil assembly are shown in the raised or hull-borne position. j

FIG. 2 is a view of the bow of a marine hydrofoil vessel from the starboard side as in FIG. 1 showing the doors which are the subject of the present invention in their fullyclosed position. The strut and foil assembly are shown in the loweredjor foil-borne position FIG. 3 is a representation of a direct bow view of a marine vessel employing the present invention as it would appear operating in the foil-borne manner.

FIG-4 is a representation of a direct bow view of a marine vessel employing the present invention as it would appear operating in the hull-borne manner.

FIG. 5 is a starboard elevation partial view of a marine vessel showing the doors which are the subject of the present invention in the open position.

FIG. 6 is a plan view illustrating the operation of the novel door closure junction portion of the doors which are the subject of the present invention as viewed at section A-A of FIG. 5. The door closure junction is shown in the closed and locked position with the ghost view depicting the same door closure junction in the unlocked and open position.

DESCRIPTION AND OPERATION OF THE INVENTION In the usual bow door assembly of a marine hydrofoil the doors are generally symmetrical. In the present invention they are not. For purposes of discussion, the invention will be described as depicted in the accompanying drawings. It is to be understood the doors could be built to be the reverse manner with the present port door built to be the starboard door and the starboard door to be the portdoor.

Referring to FIG. 1, a port door assembly 10 carried by first hinge means 11 and a starboard door assembly 12 carried by second hinge means 13 are hinged in a conventional manner where they meet the hull of a marine hydrofoil vessel 14. A port actuating assembly 16 is operably attached to the hull of the marine hydrofoil vessel 14 and the port door assembly 10. A starboard actuating assembly 17 is operably attached to the hull of the marine hydrofoil vessel 14 and the starboard door assembly 12. By means of these two actuating assemblies I6 and 17 the door assemblies 10 and 12 can be opened and held open as shown in FIG. I or closed and held closed as shown in FIGS. 2, 3, and 4. When the door assemblies It) and I2 are fully opened as shown in FIG. I the strut and foil assembly 18 can be moved either direction through its arc of operation from the fully raised position shown in FIG. 1 and FIG. 4 to the fully down position shown in FIG. 2 and FIG. 3.

More particularly in reference to the closure junction, the port door assembly I0 is equipped with a locking assembly 20 located on port interfacing edge plate 22 shown in FIG. I. The starboard door assembly 12 is equipped with matching starboard lock plates 24 located on starboard interfacing edge plate 26.

Referring to the detailed drawing of the door closure junction of FIG. 6 which represents the extreme portions of door assemblies I0 and I2 opposite the hinges about which the doors pivot, the port door assembly III is constructed to form the complete bow portion of the marine hydrofoil I4. A port main exterior plate 28 follows the desired hull shape of the port bow of the marine hydrofoil 14. A port minor exterior plate 30 is fastened to the extreme bow edge of the port main exterior plate 28 so as to form the extreme aerodynamic bow edge of the marine hydrofoil I4 and desired hull shape of the starboard bow up to a starboard exterior plate 32. The hook shaped joint or folded back portion formed by the joining of port main exterior plate 28 and port minor exterior plate 30 is strengthened by the attachment of a bow spanning member 34 and a keel member 36. The starboard exterior plate 32 follows the desired hull shape ofthe starboard bow for the portion of the starboard bow provided by the door assemblies I0 and 12 which is not provided by port minor exterior plate 30. A port interior plate 38 and a starboard interior plate 40 are fastened to port main exterior plate 28 and starboard exterior plate 32 respectively with spacer plates 42 to provide a smooth interior surface and strength. The port interfacing edge plate 22 (which is an extension of port interior plate 38) is fastened between the forward edge of the port interior plate 38 and the bow spanning member 34 at the junction of the bow spanning member 34 and the keel member 36 for strength. The starboard interfacing edge plate 26 is fastened between the forward edges of the starboard exterior plate 32 and the starboard interior plate 40 substantially parallel to the port interfacing edge plate 22.

The closure thus constructed is characterized by a strong leading edge to the bow of the marine hydrofoil I4 formed by the joining of port main exterior plate 28, port minor exterior plate 30, and keel member 36; a narrow opening subject to shearing forces at the juncture where port minor exterior plate 30 abuts starboard exterior plate 32; and, a large parallel interfacing surface area for a locking device provided by starboard interfacing plate 26 and port interfacing plate 22.

Referring to FIG. I and FIG. 6, the locking assembly 20 is operably attached to the port interfacing plate 22. Energization of actuator 44 in response to an unlocking signal will cause locking rods 46 to move into the actuator 44. Energization of actuator 44 in response to a locking signal will cause locking rods 46 to move out of the actuator 44. When the door assemblies If} and I2 are in their fully closed position and locking rods 46 are fully extended from actuator 44, locking rods 46 pass through starboard locking plates 24 and port locking plates 48 locking the door assemblies I0 and 12 in the closed position. When locking rods 46 are fully retracted into actuator 44 the door assemblies 10 and 12 are unlocked and free to move.

What has been described heretofore is the preferred embodiment of a door closure junction for a marine, air, or surface vessel as employed in the bow doors of a marine hydrofoil vessel wherein a pair of doors are both operable and the leading edge of marine hydrofoil vessel is contained completely in the structure of one of said doors. It is to be understood that the functions and construction of the port and starboard door assemblies l0 and 12 as herein before described are interchangable.

What is claimed, therefore, is:

I. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface comprismg:

a. a first door and a second door, said first door and said second door cooperating when in a closed position to form a portion of the bow aerodynamic shape of the hydrofoil vessel, said first door and said second door movable to an open position wherein the strut of the hydrofoil vessel is free to move within the bow slot opening between the fully lowered strut position and the fully raised strut position;

b. first hinge means operably attaching said first door to the hydrofoil vessel on the starboard side of the bow slot opening;

0. second hinge means operably attaching said second door to the hydrofoil vessel on the port side of the bow slot opening; and

d. means for moving said first door and said second door between said open position and said closed position in combination and for holding said first door and said second door stationary in any desired position operably attached to said first door, said second door, and the hydrofoil vessel.

2. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface as claimed in claim I wherein, additionally, means for locking said first door to said second door in said closed position are carried by said first door and said second door.

3. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface as claimed in claim I wherein:

a. each of said doors is a composite structure including an exterior surface plate, a plurality of spacer means carried by said exterior surface plate, and an interior surface plate carried by said spacer means;

b. the extreme portion of said first door opposite said first hinge means is so shaped as to form an aerodynamic edge of the vessel and is in general hook shaped wherein the exterior surface plate of said first door forming the exterior surface of the vessel on one side of the vessel in the area occupied by said first door is folded back along said aerodynamic edge of the vessel so as to form a portion of the exterior surface of the vessel on the other side of the vessel occupied by said second door;

c. first locking means are carried by said first door and disposed adjacent to said interior surface plate of said first door within said hook shaped portion of said first door; and,

d. the extreme portion of said second door opposite said second hinge means carries second locking means and is so shaped as to provide a surface upon which said second locking means is attached so that said second locking means can operably interact with said first locking means when said first door and said second door are operably disposed to be in a closed position. 4. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the 10 bow slot opening with a drag reducing surface as claimed in claim 3 wherein one of said spacer means is a keel member of the hydrofoil vessel. 

1. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface comprising: a. a first door and a second door, said first door and said second door cooperating when in a closed position to form a portion of the bow aerodynamic shape of the hydrofoil vessel, said first door and said second door movable to an open position wherein the strut of the hydrofoil vessel is free to move within the bow slot opening between the fully lowered strut position and the fully raised strut position; b. first hinge means operably attaching said first door to the hydrofoil vessel on the starboard side of the bow slot opening; c. second hinge means operably attaching said second door to the hydrofoil vessel on the port side of the bow slot opening; and d. means for moving said first door and said second door between said open position and said closed position in combination and for holding said first door and said second door stationary in any desired position operably attached to said first door, said second door, and the hydrofoil vessel.
 2. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface as claimed in claim 1 wherein, additionally, means for locking said first door to said second door in said closed position are carried by said first door and said second door.
 3. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface as claimed in claim 1 wherein: a. each of said doors is a composite structure including an exterior surface plate, a plurality of spacer means carried by said exterior surface plate, and an interior surface plate carried by said spacer means; b. the extreme portion of said first door opposite said first hinge means is so shaped as to form an aerodynamic edge of the vessel and is in general hook shaped wherein the exterior surface plate of said first door forming the exterior surface of the vessel on one side of the vessel in the area occupied by said first door is folded back along said aerodynamic edge of the vessel so as to form a portion of the exterior surface of the vessel on the other side of the vessel occupied by said second door; c. first locking means are carried by said first door and disposed adjacent to said interior surface plate of said first door within said hook shaped portion of said first door; and, d. the extreme portion of said second door opposite said second hinge means carries second locking means and is so shaped as to provide a surface upon which said second locking means is attached so that said second locking means can operably interact with said first locking means when said first door and said second door are operably disposed to be in a closed position.
 4. In a hydrofoil vessel having a bow slot opening and a bow strut moving through the bow slot opening between a fully lowered strut position and a fully raised strut position, apparatus for covering a portion of the bow slot opening with a drag reducing surface as claimed in claim 3 wherein one of said spacer means is a keel member of the hydrofoil vessel. 